Use of Washers on oblong hole

[sglynn]

On my HS rib to spar attach point, where four 1/8 inch universal rivets are used, one of my rivet holes on the rib is slightly oblong. The mating holes on the spar and other rib are fine. Can I put a washer on the univeral rivet and use a longer rivet? Oris it not a problem for the shop head? Or is there some other thing I can do, rather than scrap the whole part. If I can use a washer, where do I buy them? thanks

[Kevin Horton]

Using a washer like this is not a standard repair technique, so there is no service history.

If this is one of the two middle holes, drill new rivet holes on each side of the bad one, in line with the other rivets, with appropriate spacing. Leave the bad hole empty, or put a rivet in it. That will give a joint that is stronger than the original one.

If this is one of the two end holes, the best bet may be to ask Vans for advice.

[Tom Martin]

For a situation like this I would cut the flange off the rib and rivet a new flange on the rib. Now you can back drill through the spar to get the holes right.

[Kyle Boatright]

Something to consider is that most rivets (and bolts for that matter) work in shear, not tension. Adding a washer under the head of a rivet or bolt fed through an oversized hole does nothing to strengthen the joint in shear, so it is pretty much a waste of time.

[jsharkey]

Originally Posted by sglynn

On my HS rib to spar attach point, where four 1/8 inch universal rivets are used, one of my rivet holes on the rib is slightly oblong. The mating holes on the spar and other rib are fine. Can I put a washer on the univeral rivet and use a longer rivet? Oris it not a problem for the shop head? Or is there some other thing I can do, rather than scrap the whole part. If I can use a washer, where do I buy them? thanks

A picture would be useful. How oblong is oblong?. The rivets swell and fill the hole. It may be enough. A washer is not a good idea for a solid rivet.
Jim Sharkey
RV6 - Wiring

[sglynn]

Thanks, the oblong hole is within the radius of the rivet head, so I'll just rivet as normal, and Van's advisor agrees. Van's also mentioned using scrap to make a piece that rivets into the two adjacent holes also. thanks